\defineregister[TopicIndex]

\defineregister[SeeTopicIndex][TopicIndex]
  [pagecommand=\gobbleoneargument]

\starttext

\samplefile{lorem}
\setregisterentry[TopicIndex][entries:1=punctuation]%
\samplefile{lorem}
\setregisterentry[SeeTopicIndex][entries:1=punctuation,entries:2={\emph{See also} marking}]%
\samplefile{lorem}

\placeregister[TopicIndex,SeeTopicIndex][n=1]

\stoptext
